A couple devastated by the loss of their unborn baby decides to adopt, taking in a girl named Esther (Isabelle Fuhrman). Almost as soon as they welcome the little girl into their home, however, an alarming series of events begins to unfold, leading Kate (Vera Farmiga) to believe that there's something wrong with the her. Concerned for the safety of her family, Kate tries to get her husband John (Peter Sarsgaard) to see past Esther's sweet façade, but her warnings go unheeded.